<!DOCTYPE html>
<html lang="zh-CN">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .clas {
            font-size: 30px;
            color: aqua;
            background-color: #fff;
        }
    </style>
</head>

<body>
    <div class="clas">你好</div>
</body>

</html>